By looking for the mechanism that allows influenza A to invade lung cells, scientists also discovered a treatment that might block the virus from taking hold there.

An infection of the lungs is called pneumonia, which is caused by bacteria, viruses, and fungi that target alveoli (air sacs that line the lung). These tiny sacs share a wall with capillaries responsible for moving oxygen molecules into the blood.

Normally, when you breathe, incoming air fills the alveoli, then the alveoli pass oxygen through to the capillaries, which then transfer oxygen into your bloodstream. When you exhale… more